Re: [PATCH] Revert "drm/amdgpu: fix vblank_time when displays are off"

[Greg KH <gregkh@linuxfoundation.org>]

On Fri, Aug 18, 2017 at 12:22:53PM -0400, Alex Deucher wrote:
> On Fri, Aug 18, 2017 at 12:16 PM, Greg KH <gregkh@linuxfoundation.org> wrote:
> > On Thu, Aug 17, 2017 at 04:36:51PM -0400, Alex Deucher wrote:
> >> This reverts commit 2dc1889ebf8501b0edf125e89a30e1cf3744a2a7.
> >>
> >> Fixes a suspend and resume regression.
> >>
> >> bug: https://bugzilla.kernel.org/show_bug.cgi?id=196615
> >> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
> >> Cc: <stable@vger.kernel.org> # 4.12.x
> >> ---
> >>  drivers/gpu/drm/amd/amdgpu/amdgpu_cgs.c | 2 --
> >>  1 file changed, 2 deletions(-)
> >
> > What is the git commit id of this patch in Linus's tree?
> 
> This patch was not reverted from Linus' tree. This is just a revert of
> this patch from the 4.12 stable tree.  The patch works fine in Linus
> tree, but causes a regression in 4.12.  The original patch in Linus'
> tree was:
> beb3777682d5c296cc15a2a424f5a7a98476def0
> which was backported to 4.12 as:
> 2dc1889ebf8501b0edf125e89a30e1cf3744a2a7
> and I'd now like to revert just the backport.

Why does the backport need to be reverted as it works properly in
Linus's tree?  Are we missing something else in 4.12-stable?  This seems
very odd...

thanks,

greg k-h